igt/pm_rps: Remove reliance on guessing the busy workload

Create an unbounded batch in order to ensure that the workload doesn't
disappear before the wait and so we should be given the RPS waitboost.

References: https://bugs.freedesktop.org/show_bug.cgi?id=97564
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
1 file changed